*{
    margin: 0;
    padding: 0;
}

body,html{
    width: 100%;
    height: 100%;
}
.nav-box{
    width: 200px;
    background: rgb(50, 65, 87);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    padding-top: 40px;
}
.nav-box ul{
    list-style: none;
    line-height: 50px;
    font-size: 14px;
    color: #ddd;
}
.nav-box ul .nav-block{
    padding-left: 10px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    flex-wrap: wrap;
    position: relative;
    font-size:20px;
    padding-top: 10px;
    margin-top: 20px;
}
.nav-box ul .nav-block:hover{
    color: #fff;
    background: rgb(40, 52, 70);
}
.nav-box ul li i{
    display: inline-block;
    width: 40px;
    height: 40px;
}
.nav-box ul li i.arrow{
    position: absolute;
    top: 5px;
    right: 5px;
}


.nav-box .nav-block.on i.arrow{
    transform: rotate(0deg);
}
.nav-box .nav-two{
    display: block;
    width: 100%;
    font-size: 13px;
    line-height: 45px;
    display: none;
}
.nav-block.on+ul.nav-two{
    display: block;
}
.nav-box .nav-two li{

    padding-left: 38px;
    cursor: pointer;
}
.nav-box .nav-two li:hover{
    background: rgb(40, 52, 70);
}
.nav-two a:link{
  color: #fff;

}
.nav-block a:link{
  color: #fff;
  }
.header{
    border: solid 1px black;
    width: 1800px;
    height: 60px;
    background: green;
    
}
.header h1{
    text-align: center ;
    font-size: 50px;
    font-family: 隶书;
    letter-spacing: 20px;
    position: relative;
}
.return {
    width:600 px;
    height: 30px;
    position: absolute;
    top: 20px;
    left: 1550px;
    font-size: 30px;
}
.return a{
    text-decoration: none;
}  
.product-image-card {
  margin-top: 30px;
  margin-left: 280px;
    max-width: 600px;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 8px 32px rgba(0,0,0,0.1);
    position: relative;
    background: #fff;
  float: left;
  }
  .image-wrapper {
    position: relative;
    aspect-ratio: 16/9;
    transition: transform 0.3s ease;
  }
  .main-image {
    width:500px;;
    height: 300px;
    object-fit: cover;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  }
  /* 悬停信息层 */
  .hover-info {
    position: absolute;
    inset: 0;
    background: linear-gradient(
      180deg, 
      rgba(0,0,0,0) 40%, 
      rgba(0,0,0,0.7) 100%
    );
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
  }
  .info-content {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 2rem;
    transform: translateY(100%);
    transition: transform 0.4s ease;
    color: white;
  }
  .spec-list {
    margin-top: 1rem;
    font-size: 0.9em;
    line-height: 1.6;
    opacity: 0;
    transition: opacity 0.3s 0.2s ease;
  }
  .info-indicator {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: rgba(255,255,255,0.9);
    padding: 0.5rem 1rem;
    border-radius: 2rem;
    font-size: 0.85em;
    opacity: 0;
    transform: translateY(-10px);
    transition: all 0.3s ease;
  }
  /* 悬停交互效果 */
  .image-wrapper:hover .hover-info {
    opacity: 1;
  }
  .image-wrapper:hover .info-content {
    transform: translateY(0);
  }
  .image-wrapper:hover .spec-list {
    opacity: 1;
  }
  .image-wrapper:hover .info-indicator {
    opacity: 1;
    transform: translateY(0);
  }
  .image-wrapper:hover .main-image {
    transform: scale(1.03);
    filter: brightness(0.95);
  }
  /* 按钮样式 */
  .detail-btn {
    width: 100%;
    padding: 1.2rem;
    background: linear-gradient(135deg, #4f46e5, #6366f1);
    color: white;
    border: none;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0.8rem;
    cursor: pointer;
    transition: all 0.3s ease;
  }
  .arrow {
    width: 20px;
    height: 20px;
    fill: currentColor;
    transition: transform 0.3s ease;
  }
  .detail-btn:hover {
    background: linear-gradient(135deg, #4338ca, #4f46e5);
  }
  .detail-btn:hover .arrow {
    transform: translateX(3px);
  }
  /* 无障碍优化 */
  @media (prefers-reduced-motion) {
    * {
      transition: none !important;
    }
  }
  .detail-btn:focus {
    outline: 3px solid rgba(99, 102, 241, 0.5);
    outline-offset: 2px;
  }